A virtualization module creates and manages one or more logical storage devices (e.g., volumes). A virtualization module can be implemented in hardware, software, or a combination of the two. VERITAS Volume Manager™ is an example of a virtualization module. Applications such as databases and file systems view and access the logical volumes managed by the virtualization module in the same way that the applications would view and access physical storage devices. By providing applications with virtualized volumes, the virtualization module obscures the details of the storage implementation from the applications. For example, the details of relatively complex storage arrangements that are used to provide improved performance and/or fault tolerance can be hidden from a file system.
Each logical volume can be implemented on one or more physical storage devices. A physical storage device can be a single device (e.g., a single hard drive, CD (Compact Disc) drive, or DVD (Digital Versatile Disc) drive). Alternatively, a storage device may include an array of such devices (e.g., a RAID array of several hard drives controlled by a hardware array controller). Also, portions of more than one logical volume can be implemented on the same physical storage device.
In order to manage a logical storage device, a virtualization module maintains volume configuration information. Typically, volume configuration information is maintained for each physical storage device used to implement the logical volume. When a storage device is corrupted, access to the volume configuration information stored on that storage device may be inhibited. This in turn can negatively impact the virtualization module's ability to access data stored in the logical volume. Accordingly, improved techniques for providing access to such volume configuration information is desired.